If they can figure out how to manage their lead costs better and perhaps sell off the US transportation business to JCI or someone else, this could turn into a similar outcome. That said, even using less optimistic assumptions, I think the equity can have a lot more value provided the company performs well in the next couple of quarters.
This one has been painful so far, but there have been trading opportunities like back in September. I believe there will be at least one more spike like that even if the recovery in the equity isn't as great I envision (if you look at other BKs like STP, Eastman Kodak, it happened a few times).
Not for the faint of heart, but keep watching the financials and see if EBITDA continues to improve.